The card reader could shout "Child! Enfant !" just like the lottery terminals that shout "Winner! Gagnon !" though the Presto card reader would use a child's voice.I think the tone for child fare should be the reader saying the word "child" clear and loud. That may introduce some shame to someone who is obviously not a child, and could be an easy fix (although who knows with Presto) that may help a little bit.